CML patients undergoing tyrosine kinase inhibitor treatment are monitored every 3 months because of the prognostic value of BCR-ABL1 relative expression levels. Early identification of treatment failure allows for a revised, potentially life-saving, therapeutic strategy. The long-term objective of this project is to gain regulatory approval for the BCR-ABL1 RT-qPCR Test as an FDA-cleared IVD to improve the availability of accurate, reliable testing to monitor residual disease in patients with CML. Clearance involves internal testing activities, manufacturing of multiple lots and precision and accuracy testing at multiple independent clinical laboratories. Asuragen has achieved agreement with the FDA on the study design, clinical endpoints and statistical approaches, which are integrated into this proposal. In the interim between the Phase I and Phase II Contracts, the contractor had supported and performed a clinical study for the validation of the BCR-ABL1 RT-qPCR Test. In Phase II, Asuragen will perform essential studies to develop and clinically validate a test for BCR-ABL1 minor breakpoint (e1a2) as well as studies for manufacturing process improvements and platform expansion studies for both the Major and minor breakpoint BCR-ABL1 RT-qPCR Tests.